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/*-
* Copyright (c) 2010 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/gpt.h>
#ifndef LITTLE_ENDIAN
#error gpt.c works only for little endian architectures
#endif
#include "stand.h"
#include "zlib.h"
#include "drv.h"
#include "gpt.h"
static struct gpt_hdr hdr_primary, hdr_backup, *gpthdr;
static uint64_t hdr_primary_lba, hdr_backup_lba;
static struct gpt_ent table_primary[MAXTBLENTS], table_backup[MAXTBLENTS];
static struct gpt_ent *gpttable;
static int curent, bootonce;
/*
* Buffer below 64kB passed on gptread(), which can hold at least
* one sector of data (512 bytes).
*/
static char *secbuf;
static void
gptupdate(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
struct gpt_ent *table)
{
int entries_per_sec, firstent;
daddr_t slba;
/*
* We need to update the following for both primary and backup GPT:
* 1. Sector on disk that contains current partition.
* 2. Partition table checksum.
* 3. Header checksum.
* 4. Header on disk.
*/
entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
slba = curent / entries_per_sec;
firstent = slba * entries_per_sec;
bcopy(&table[firstent], secbuf, DEV_BSIZE);
slba += hdr->hdr_lba_table;
if (drvwrite(dskp, secbuf, slba, 1)) {
printf("%s: unable to update %s GPT partition table\n",
BOOTPROG, which);
return;
}
hdr->hdr_crc_table = crc32(0, Z_NULL, 0);
hdr->hdr_crc_table = crc32(hdr->hdr_crc_table, (const Bytef *)table,
hdr->hdr_entries * hdr->hdr_entsz);
hdr->hdr_crc_self = crc32(0, Z_NULL, 0);;
hdr->hdr_crc_self = crc32(hdr->hdr_crc_self, (const Bytef *)hdr,
hdr->hdr_size);
bzero(secbuf, DEV_BSIZE);
bcopy(hdr, secbuf, hdr->hdr_size);
if (drvwrite(dskp, secbuf, hdr->hdr_lba_self, 1)) {
printf("%s: unable to update %s GPT header\n", BOOTPROG, which);
return;
}
}
int
gptfind(const uuid_t *uuid, struct dsk *dskp, int part)
{
struct gpt_ent *ent;
int firsttry;
if (part >= 0) {
if (part == 0 || part > gpthdr->hdr_entries) {
printf("%s: invalid partition index\n", BOOTPROG);
return (-1);
}
ent = &gpttable[part - 1];
if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0) {
printf("%s: specified partition is not UFS\n",
BOOTPROG);
return (-1);
}
curent = part - 1;
goto found;
}
firsttry = (curent == -1);
curent++;
if (curent >= gpthdr->hdr_entries) {
curent = gpthdr->hdr_entries;
return (-1);
}
if (bootonce) {
/*
* First look for partition with both GPT_ENT_ATTR_BOOTME and
* GPT_ENT_ATTR_BOOTONCE flags.
*/
for (; curent < gpthdr->hdr_entries; curent++) {
ent = &gpttable[curent];
if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
continue;
if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTME))
continue;
if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTONCE))
continue;
/* Ok, found one. */
goto found;
}
bootonce = 0;
curent = 0;
}
for (; curent < gpthdr->hdr_entries; curent++) {
ent = &gpttable[curent];
if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
continue;
if (!(ent->ent_attr & GPT_ENT_ATTR_BOOTME))
continue;
if (ent->ent_attr & GPT_ENT_ATTR_BOOTONCE)
continue;
/* Ok, found one. */
goto found;
}
if (firsttry) {
/*
* No partition with BOOTME flag was found, try to boot from
* first UFS partition.
*/
for (curent = 0; curent < gpthdr->hdr_entries; curent++) {
ent = &gpttable[curent];
if (bcmp(&ent->ent_type, uuid, sizeof(uuid_t)) != 0)
continue;
/* Ok, found one. */
goto found;
}
}
return (-1);
found:
dskp->part = curent + 1;
ent = &gpttable[curent];
dskp->start = ent->ent_lba_start;
if (ent->ent_attr & GPT_ENT_ATTR_BOOTONCE) {
/*
* Clear BOOTME, but leave BOOTONCE set before trying to
* boot from this partition.
*/
if (hdr_primary_lba > 0) {
table_primary[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTME;
gptupdate("primary", dskp, &hdr_primary, table_primary);
}
if (hdr_backup_lba > 0) {
table_backup[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTME;
gptupdate("backup", dskp, &hdr_backup, table_backup);
}
}
return (0);
}
static int
gptread_hdr(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
uint64_t hdrlba)
{
uint32_t crc;
if (drvread(dskp, secbuf, hdrlba, 1)) {
printf("%s: unable to read %s GPT header\n", BOOTPROG, which);
return (-1);
}
bcopy(secbuf, hdr, sizeof(*hdr));
if (bcmp(hdr->hdr_sig, GPT_HDR_SIG, sizeof(hdr->hdr_sig)) != 0 ||
hdr->hdr_lba_self != hdrlba || hdr->hdr_revision < 0x00010000 ||
hdr->hdr_entsz < sizeof(struct gpt_ent) ||
hdr->hdr_entries > MAXTBLENTS || DEV_BSIZE % hdr->hdr_entsz != 0) {
printf("%s: invalid %s GPT header\n", BOOTPROG, which);
return (-1);
}
crc = hdr->hdr_crc_self;
hdr->hdr_crc_self = crc32(0, Z_NULL, 0);
if (crc32(hdr->hdr_crc_self, (const Bytef *)hdr, hdr->hdr_size) !=
crc) {
printf("%s: %s GPT header checksum mismatch\n", BOOTPROG,
which);
return (-1);
}
hdr->hdr_crc_self = crc;
return (0);
}
void
gptbootfailed(struct dsk *dskp)
{
if (!(gpttable[curent].ent_attr & GPT_ENT_ATTR_BOOTONCE))
return;
if (hdr_primary_lba > 0) {
table_primary[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
table_primary[curent].ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
gptupdate("primary", dskp, &hdr_primary, table_primary);
}
if (hdr_backup_lba > 0) {
table_backup[curent].ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
table_backup[curent].ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
gptupdate("backup", dskp, &hdr_backup, table_backup);
}
}
static void
gptbootconv(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
struct gpt_ent *table)
{
struct gpt_ent *ent;
daddr_t slba;
int table_updated, sector_updated;
int entries_per_sec, nent, part;
table_updated = 0;
entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
for (nent = 0, slba = hdr->hdr_lba_table;
slba < hdr->hdr_lba_table + hdr->hdr_entries / entries_per_sec;
slba++, nent += entries_per_sec) {
sector_updated = 0;
for (part = 0; part < entries_per_sec; part++) {
ent = &table[nent + part];
if ((ent->ent_attr & (GPT_ENT_ATTR_BOOTME |
GPT_ENT_ATTR_BOOTONCE |
GPT_ENT_ATTR_BOOTFAILED)) !=
GPT_ENT_ATTR_BOOTONCE) {
continue;
}
ent->ent_attr &= ~GPT_ENT_ATTR_BOOTONCE;
ent->ent_attr |= GPT_ENT_ATTR_BOOTFAILED;
table_updated = 1;
sector_updated = 1;
}
if (!sector_updated)
continue;
bcopy(&table[nent], secbuf, DEV_BSIZE);
if (drvwrite(dskp, secbuf, slba, 1)) {
printf("%s: unable to update %s GPT partition table\n",
BOOTPROG, which);
}
}
if (!table_updated)
return;
hdr->hdr_crc_table = crc32(0, Z_NULL, 0);
hdr->hdr_crc_table = crc32(hdr->hdr_crc_table, (const Bytef *)table,
hdr->hdr_entries * hdr->hdr_entsz);
hdr->hdr_crc_self = crc32(0, Z_NULL, 0);
hdr->hdr_crc_self = crc32(hdr->hdr_crc_self, (const Bytef *)hdr,
hdr->hdr_size);
bzero(secbuf, DEV_BSIZE);
bcopy(hdr, secbuf, hdr->hdr_size);
if (drvwrite(dskp, secbuf, hdr->hdr_lba_self, 1))
printf("%s: unable to update %s GPT header\n", BOOTPROG, which);
}
static int
gptread_table(const char *which, struct dsk *dskp, struct gpt_hdr *hdr,
struct gpt_ent *table)
{
struct gpt_ent *ent;
int entries_per_sec;
int part, nent;
daddr_t slba;
if (hdr->hdr_entries == 0)
return (0);
entries_per_sec = DEV_BSIZE / hdr->hdr_entsz;
slba = hdr->hdr_lba_table;
nent = 0;
for (;;) {
if (drvread(dskp, secbuf, slba, 1)) {
printf("%s: unable to read %s GPT partition table\n",
BOOTPROG, which);
return (-1);
}
ent = (struct gpt_ent *)secbuf;
for (part = 0; part < entries_per_sec; part++, ent++) {
bcopy(ent, &table[nent], sizeof(table[nent]));
if (++nent >= hdr->hdr_entries)
break;
}
if (nent >= hdr->hdr_entries)
break;
slba++;
}
if (crc32(0, (const Bytef *)table, nent * hdr->hdr_entsz) !=
hdr->hdr_crc_table) {
printf("%s: %s GPT table checksum mismatch\n", BOOTPROG, which);
return (-1);
}
return (0);
}
int
gptread(struct dsk *dskp, char *buf)
{
uint64_t altlba;
/*
* Read and verify both GPT headers: primary and backup.
*/
secbuf = buf;
hdr_primary_lba = hdr_backup_lba = 0;
curent = -1;
bootonce = 1;
dskp->start = 0;
if (gptread_hdr("primary", dskp, &hdr_primary, 1) == 0 &&
gptread_table("primary", dskp, &hdr_primary, table_primary) == 0) {
hdr_primary_lba = hdr_primary.hdr_lba_self;
gpthdr = &hdr_primary;
gpttable = table_primary;
}
if (hdr_primary_lba > 0) {
/*
* If primary header is valid, we can get backup
* header location from there.
*/
altlba = hdr_primary.hdr_lba_alt;
} else {
altlba = drvsize(dskp);
if (altlba > 0)
altlba--;
}
if (altlba == 0)
printf("%s: unable to locate backup GPT header\n", BOOTPROG);
else if (gptread_hdr("backup", dskp, &hdr_backup, altlba) == 0 &&
gptread_table("backup", dskp, &hdr_backup, table_backup) == 0) {
hdr_backup_lba = hdr_backup.hdr_lba_self;
if (hdr_primary_lba == 0) {
gpthdr = &hdr_backup;
gpttable = table_backup;
printf("%s: using backup GPT\n", BOOTPROG);
}
}
/*
* Convert all BOOTONCE without BOOTME flags into BOOTFAILED.
* BOOTONCE without BOOTME means that we tried to boot from it,
* but failed after leaving gptboot and machine was rebooted.
* We don't want to leave partitions marked as BOOTONCE only,
* because when we boot successfully start-up scripts should
* find at most one partition with only BOOTONCE flag and this
* will mean that we booted from that partition.
*/
if (hdr_primary_lba != 0)
gptbootconv("primary", dskp, &hdr_primary, table_primary);
if (hdr_backup_lba != 0)
gptbootconv("backup", dskp, &hdr_backup, table_backup);
if (hdr_primary_lba == 0 && hdr_backup_lba == 0)
return (-1);
return (0);
}